golang-exercises/select-buttons/main.go

package main

import (
	"fmt"
	"log"
	"time"

	"github.com/jroimartin/gocui"
)

var (
	viewArr = []string{"exercise1", "exercise2"}
	active  = 0
)

func main() {
	g, err := gocui.NewGui(gocui.OutputNormal)
	if err != nil {
		log.Panicln(err)
	}
	defer g.Close()
	g.Highlight = true
	g.SelFgColor = gocui.ColorRed
	g.SetManagerFunc(layout)
	initKeybindings(g)
	if err := g.MainLoop(); err != nil && err != gocui.ErrQuit {
		log.Panicln(err)
	}
}

func quit(*gocui.Gui, *gocui.View) error {
	return gocui.ErrQuit
}

func initKeybindings(g *gocui.Gui) error {
	if err := g.SetKeybinding("", gocui.KeyCtrlC, gocui.ModNone, quit); err != nil {
		log.Panicln(err)
	}
	if err := g.SetKeybinding("", gocui.KeyTab, gocui.ModNone, nextView); err != nil {
		log.Panicln(err)
	}
	if err := g.SetKeybinding("", gocui.KeyEnter, gocui.ModNone, buttonSelect); err != nil {
		log.Panicln(err)
	}
	return nil
}

func buttonSelect(g *gocui.Gui, v *gocui.View) error {
	exercise1, err := g.View("exercise1")
	if err != nil {
		return err
	}
	exercise2, err := g.View("exercise2")
	if err != nil {
		return err
	}
	switch v {
	case exercise1:
		g.Close()
		exer1()
		time.Sleep(time.Second)
		main()
	case exercise2:
		fmt.Fprintln(v, "BAR")
	}
	return nil
}

func layout(g *gocui.Gui) error {
	//maxX, maxY := g.Size()
	if exercise1, err := g.SetView("exercise1", 2, 1, 12, 4); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		exercise1.Title = "Ex. 1"
		g.SetCurrentView("exercise1")
		fmt.Fprintln(exercise1, "Methods")
	}
	if exercise2, err := g.SetView("exercise2", 14, 1, 24, 4); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		exercise2.Title = "Ex. 2"
	}

	return nil
}

func nextView(g *gocui.Gui, v *gocui.View) error {
	nextIndex := (active + 1) % len(viewArr)
	name := viewArr[nextIndex]

	if _, err := setCurrentViewOnTop(g, name); err != nil {
		return err
	}

	active = nextIndex
	return nil
}

func setCurrentViewOnTop(g *gocui.Gui, name string) (*gocui.View, error) {
	if _, err := g.SetCurrentView(name); err != nil {
		return nil, err
	}
	return g.SetViewOnTop(name)
}